1. Technical Field of the Invention
The present invention relates to a method and system for implementing services in a telecommunications network, and in particular for transferring, upon detection of a trigger condition, portable code from one telecommunications node to another in an intelligent network and executing the code at the latter node.
2. Description of Related Art
As stored program-controlled (SPC) switching systems have evolved, a wide variety of useful features have been developed to extend the communication capabilities such systems provide. Such services or features include call forwarding, "800" or toll free services, call screening, and the like. With the development and improvement of sophisticated telecommunications applications, the telecommunications industry has adopted the term "intelligent network" (IN) to denote a concept and architecture for providing standardized interfaces between the service logic and the switching system of a multi-vendor telecommunications network. The goals of the IN are to centralize the service execution in a control node within a telecommunications network to provide rapid definition, testing and introduction of new services as well as to simplify the modification of existing services. IN also provides greater flexibility in the design and development of new services in a multi-vendor environment with shorter lead time and standard network interfaces.
The basic concept behind IN is to move the "intelligence" out of each local exchange or Service Switching Point (SSP) and centralize the services providing the intelligence in a Service Control Point (SCP). At specific points during the processing and execution of a call in an IN telecommunications system, the SSP determines whether certain trigger conditions are met. These trigger conditions, for instance, might include the initiation of a call, the receipt of an abbreviated dialing code, or the receipt of an indication that a called station is currently busy. If no trigger conditions are met, then the SSP proceeds according to normal call processing. Otherwise, if certain trigger conditions are met, the SSP sends a query over a network, such as a Signaling System No. 7 (SS7) network, to the SCP requesting instructions on how to proceed with processing of the call. The SCP responds to the request by executing one or more service features contained in a service library associated with the SCP. Then, an instruction or set of instructions are sent from the SCP to the SSP informing the SSP on how to proceed. The ongoing call is further processed by the SSP according to these instructions.
Despite efforts to permit more rapid introduction of new services and greater service flexibility through use of IN, significant barriers still exist to the introduction of new or more customized services into the IN. First, although it is easier to add new intelligence to the SCP (as permitted in IN systems) rather than to the switch itself (as in pre-IN systems), IN still requires that new or revised protocols be developed and introduced to enable widespread introduction of new services in a multi-vendor environment. The development and implementation of new protocols, however, can take years in some cases and can cause significant delays in the introduction of new services.
Alternatively, new services can be implemented on a proprietary (i.e., single vendor) basis. The use of proprietary services, however, generally precludes widespread availability of the services. Network operators typically use components from multiple vendors. An incompatibility of components from different vendors can sometimes prevent operators from being able to implement proprietary services. Furthermore, even where a particular operator is able to offer proprietary services, wireless subscribers will often not be able to access those services when they are roaming in visited networks, again, because of incompatibility problems.
There is a need, therefore, for a system and method that would permit new services to be introduced into a multi-vendor environment without requiring a corresponding introduction of new standards. In addition, there is a need for a system and method that would permit the development and introduction of more flexible and/or subscriber-customized service features. Preferably, such a system and method could be utilized across different networks without having to develop standardized interfaces.